688647 has 4 divisors (see below), whose sum is σ = 918200. Its totient is φ = 459096.

The previous prime is 688637. The next prime is 688657. The reversal of 688647 is 746886.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (688637) and next prime (688657).

It is not a de Polignac number, because 688647 - 2⁴ = 688631 is a prime.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (688627) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 114772 + ... + 114777.

It is an arithmetic number, because the mean of its divisors is an integer number (229550).

2⁶⁸⁸⁶⁴⁷ is an apocalyptic number.

688647 is a deficient number, since it is larger than the sum of its proper divisors (229553).

688647 is a wasteful number, since it uses less digits than its factorization.

688647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 229552.

The product of its digits is 64512, while the sum is 39.

The square root of 688647 is about 829.8475763657. The cubic root of 688647 is about 88.3077636525.

The spelling of 688647 in words is "six hundred eighty-eight thousand, six hundred forty-seven".